Previous HGNC Symbols for ITPA Gene

Previous GeneCards Identifiers for ITPA Gene

Summaries for ITPA Gene

Entrez Gene Summary for ITPA Gene

This gene encodes an inosine triphosphate pyrophosphohydrolase. The encoded protein hydrolyzes inosine triphosphate and deoxyinosine triphosphate to the monophosphate nucleotide and diphosphate. This protein, which is a member of the HAM1 NTPase protein family, is found in the cytoplasm and acts as a homodimer. Defects in the encoded protein can result in inosine triphosphate pyrophosphorylase deficiency which causes an accumulation of ITP in red blood cells. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Jun 2012]

UniProtKB/Swiss-Prot for ITPA Gene

Pyrophosphatase that hydrolyzes the non-canonical purine nucleotides inosine triphosphate (ITP), deoxyinosine triphosphate (dITP) as well as 2-deoxy-N-6-hydroxylaminopurine triposphate (dHAPTP) and xanthosine 5-triphosphate (XTP) to their respective monophosphate derivatives. The enzyme does not distinguish between the deoxy- and ribose forms. Probably excludes non-canonical purines from RNA and DNA precursor pools, thus preventing their incorporation into RNA and DNA and avoiding chromosomal lesions.

UniProtKB/Swiss-Prot

Inosine triphosphate pyrophosphohydrolase deficiency (ITPAD) [MIM:613850]: A common inherited condition characterized by the abnormal accumulation of inosine triphosphate in erythrocytes. It might have pharmacogenomic implications and be related to increased drug toxicity of purine analog drugs. {ECO:0000269 PubMed:12384777, ECO:0000269 PubMed:12436200, ECO:0000269 Ref.2}. Note=The disease is caused by mutations affecting the gene represented in this entry. Three different human populations have been reported with respect to their ITPase activity: high, mean (25% of high) and low activity. The variant Thr-32 is associated with complete loss of enzyme activity, may be by altering the local secondary structure of the protein. Heterozygotes for this polymorphism have 22.5% of the control activity: this is consistent with a dimeric structure of the enzyme.